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Module 03 · 0/40
Module 03
Arrays: From Fundamentals to Advanced
0/40
16
19
5
Fundamentals & Basic Operations
0/5
1
Find Largest Element
Easy
2
Find Second Largest Element
Easy
3
Check if Array is Sorted
Easy
4
Remove Duplicates from Sorted Array
Easy
5
Linear Search
Easy
Logic Building: Rotations & Sets
0/7
1
Left Rotate Array by One
Easy
2
Rotate Array by K Places
Easy
3
Move Zeros to End
Easy
4
Union of Two Sorted Arrays
Med.
5
Find Missing Number
Easy
6
Max Consecutive Ones
Easy
7
Find the Single Number
Med.
Two Pointers & Sliding Window
0/5
1
Longest Subarray with Sum K (Positives)
Med.
2
Longest Subarray with Sum K (Mixed)
Med.
3
Two Sum
Med.
4
Sort Colors (Dutch National Flag)
Med.
5
Rearrange Array by Sign
Med.
Greedy & Kadane's Algorithm
0/5
1
Majority Element (>N/2)
Easy
2
Maximum Subarray Sum (Kadane's Algorithm)
Easy
3
Print Maximum Sum Subarray
Med.
4
Maximum Product Subarray
Easy
5
Best Time to Buy and Sell Stock
Easy
Advanced Array Logic
0/3
1
Next Permutation
Med.
2
Leaders in an Array
Easy
3
Longest Consecutive Sequence
Med.
2D Arrays (Matrices)
0/3
1
Set Matrix Zeroes
Med.
2
Rotate Matrix 90 Degrees
Med.
3
Spiral Matrix Traversal
Med.
Hard Problems: N-Sum & Hashing
0/7
1
Count Subarray Sum Equals K
Easy
2
Largest Subarray with 0 Sum
Med.
3
Count Subarrays with XOR K
Hard
4
Pascal's Triangle
Med.
5
Majority Element (>N/3)
Med.
6
Three Sum
Med.
7
Four Sum
Hard
Hard Problems: Merge & Intervals
0/5
1
Merge Overlapping Intervals
Med.
2
Merge Sorted Arrays Without Extra Space
Med.
3
Find Missing and Repeating Numbers
Hard
4
Count Inversions
Hard
5
Reverse Pairs
Hard